Together with Professor Fritz Vahrenholt, Dr. Lüning authored the important 2013 book The Neglected Sun: How the Sun Precludes Climate Catastrophe. Dr. Vahrenholt’s “defection” caused seismic quakes in the climate alarmist ranks, since he was a founding father of Germany’s environmental movement and a director of one of Europe’s largest alternative energy companies. On June 18, 2012, just two days before the opening of United Nations’ Rio+20 Earth Summit, Vahrenholt sent a shock through the green ranks with an op-ed in Britain’s Telegraph entitled “Global warming: second thoughts of an environmentalist.” Vahrenholt took special aim at the UN’s now thoroughly discredited Intergovernmental Panel on Climate Change (IPCC).